Accurate diagnosis of various neurological disorders, and especially neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis (ALS), Huntington's disease, Creutzfeldt-Jacob disease or progressive supranuclear palsy (PSP), and specifically in the early stages of disease, is often a substantial challenge for the clinical neurologist. The tools available for the clinical neurologist for that purpose comprise the patient's medical history, the reported symptoms, the findings in the neurological examination and ancillary examinations, such as brain computerized tomography (CT scan) or magnetic resonance imaging (MRI). Taken together, currently these tools are often insufficient, and are often capable of reflecting the underlying neuropathological processes only at relatively late stages of disease. Another challenge often encountered in the clinical neurological practice is the monitoring of response of brain tumors to treatment. Therefore, in order to make an accurate diagnosis, to devise therapy, to follow disease course or to assess the effect of treatment in any of the above serious and debilitating neurological disorders, there is therefore clearly a need for novel, non-invasive methods, for detection and imaging of neuropathological processes.
Molecular imaging is a novel and rapidly-developing field, concerning the use of molecular probes, comprising a marker for imaging, which can report via non-invasive clinical imaging procedures, such as positron emission tomography (PET scan), on cellular processes associated with health and disease. Oxidative stress is one of the hallmarks in the pathogenesis of many medical disorders. Cellular damage due to oxygen free radicals has been shown to play an important role in neurodegeneration. Apoptosis is linked to oxidative stress both at the level of triggering of the death process, since oxidative stress is a potent inducer of the death program; and at the level of execution of cell death, as dramatic alterations in mitochondrial function, and breakdown of cellular anti-oxidant mechanisms are universally encountered during apoptosis. To date, there is no tool in clinical practice for molecular imaging of oxidative stress.